Refrigeration machine



y 2, 1953 c. D. RUSSELL 2,637,981

REFRIGERATION MACHINE Filed Dec. 30, 1948 4 Sheets-Sheet 1 FIG. l

Inventor: CARL D. R USSELL Aflo rney May 12, 1953 c. D. RUSSELL2,637,981

REFRIGERATION MACHINE Filed Dec. 50, 1948 4 Sheets-Sheet 2 4 -sf sInventor: CARL D. RUSSELL,

. Attorney y 12, 1953 c. D. RUSSELL 2,637,981

REFRIGERATION MACHINE Filed Dec. 30, 1948 4 Sheets-Sheet 4 FIG. 7

CA 24 /RV k I28 I 9 I00 I29 87 9? FIG 8 RV CA 3| a CB INVENTOR CARL D.RUSSELL;

94 ATTORNEY Patented May 12, 1953 UNITED S'E'A'E'Efi PATENT @FMQEREFRIGERATION MACHIN E Carl D. Russell, Muskogee, Okla, assignor of fiveper cent to G. G. Pool, Muskogee, Okla.

Application December 36, 1948, Serial N0."68;1 i1

(Cl. (WP-d.)

19 Claims. 1

This invention. relates to improvements in refrigeration apparatus, andmore particularly to improved refrigeration apparatus employinga singlesupply of refrigerant serving as a motive fluid for the compressor asWell as providing refrigeration effect.

Broadly stated, it is a principal object of the invention to provide aneflicient, practical thoroughly dependable heat-operated mechanicalrefrigeration apparatus of the type employing a low boiling pointrefrigerant which when heated provides a high pressure vapor serving asthe driving or motive for the compressor.

The invention also aims to provide an it ved nzotomcontpressor unit foruse in refrigeration apparatus of the stated character, which is sodesigned and constructed to efllciently utilise the energy of the highpressure refrigerant vapor in driving the compressor component of theunit.

The invention also contemplates a novel, integrated system of controlsfor a heat-operated reration appar'tus described, which proin. the firstinstance for the supply of a metered. volume of fuel to the heat ourcein ac our use with the cooling effect desired, and the ET!" .ssion ofrefrigerant vapor to the motorcoinpressor unit at the requisite pressureto motivate the same against the condenser pressure.

Yet another object of the invention is :to proan improved and efficientmeans powered by the high pressure refrigerant vapor for supplyingmake-up liquefied refrigerant to the generator or boiler in accordancewith the demands of the apparatus.

The above and other objects and features of advantage of the inventionwill be seen from the following detailed description, taken with theaccompanying drawings, wherein Fig. 1 is a diagrammatic viewillustrating an improved refrigeration apparatus according to thisinvetnion, together with the controls therefor;

Figs. 2 and 3 are longitudinal sections taken through the improvedmotor-compressor unit according to the invention, Fig. 3 illustratingthe valve reversing function of the pistons;

Fig. 4: is a section taken along line 4 i of 5 and 6 are, respectively,elevation and vertical sectional views of the fuel metering Valve andcontrols associated therewith;

Figs. '7, 8 and 9 are vertical. sectional views illustrating theanti-perco1ating or pressure regulating valve functioning to insure therequisite high pressure of refrigerant vapor supplied to themotor-compressor unit; and i Figs. 10 and 11 are vertical sectionalviews taken through the twin fuel injectors, illustrating theiralternate operation by pressure supplied from the motor-compressor unit.

Referring to the drawings, wherein like reference characters designatelike parts throughout the several views, a generalized description ofthe improved refrigeration apparatus as a whole will first be given, tobe followed fey a more detailed description of the component partsmaking up the same.

In Fig. 1, illustrating diagrammatically the apparatus as a whole,reference character B designates a boiler or generator of high pressurevapor, shown to comprise a heating vessel it enclosed within the shellof a small heater or furnace is, the heat source therefor being shown asa main burner 12 and a pilot burner It. The heated products ofcombustion are conducted from the heater by a flue generally designatedI l. Liquefied make-up refrigerant is supplied to the boiler Balternately through lines l5, It from a receiver 1?, through a liquidline I! connected into a com-- mon supply line If extending betweenand-delivering to twin injectors I1, I2 (Figs. 10 and 11), to thedischarge sides of which the make-up lines l5, iii are connected.

The liquid refrigerant is vaporized in the boiler B, and the highpressure vapor is conducted from the boiler through line 262 to ananti-percolating or pressure regulating valve RV (Figs. 7, 8 and 9)which function to regulate the pressure at which the refrigerant vaporgenerated in the boiler is supplied toa motor-compressor unit MC (Figs.2

and 3). Assuming the pressure of the vapor to have reached apredetermined high value, the regulating valve RV opens to pass the highpressure vapor through line 2i which re-enters the boiler and connectswith a secondary heater 22 contained in its flue section it, whereinsuperheat is added and any entrained liquid is vaporized. From thesecondary heater, the superheated high pressure refrigerant vapor isconducted to the motor-compressor unit MC through supply line 24.

As will be described, the motor-compressor unit MO is of the connectedpiston type, the two pistons thereof being alternately driven by thehigh pressure refrigerant vapor to compress the warm or low pressurerefrigerant vapor drawn from the evaporator E, the compressordischarging through lines 26, 27 connected to the opposite ends of themotor-compressor cylinder into a common line 28 into which also connectsan exhaust line 28a extending into the midportion of the cylinder of themotor-compressor unit. The com pressed refrigerant vapor passes fromcommon line 28 through line 29 to a condenser C, from which theliquefied refrigerant may drain to receiver R. through line 30.Liquefied refrigerant is conducted from receiver R to pressureregulating valve RV through line 3|, and to the evaporator E throughline 32 wherein, in providing cooling effect, it vaporizes underrelatively low pressure, the low pressure vapor being drawn from theevaporator through line 34 into a common line 35 delivering tocompressor inlet lines 36, 37, connected to the ends of themotor-compressor cylinder.

The burners l2, l3 are supplied with gas through individual supply lines|2a and I30. under the control of a fuel metering valve MV, to which gassupply line SL delivers. As will be later described, fuel (heating gas)is supplied to the pilot burner l3 at a constant low rate through themetering valve MV, and fuel is supplied to the main burner |2 throughline |2a under the control of the metering valve, whose functioning iscontrolled conjointly by a thermostatic control TC responding to therate of evaporation in the evaporator E and a supervisory controlgenerally designated SC responding to the intended functioning of theregulating valve RV. The twin injectors I1, I2 are alternately operatedin response to the differences in pressure existing in the power orinner-end spaces of the motor-compressor unit MC, and, to this end,take-off lines 38, 39 are connected to said cylinder, of which line 38connects into branch lines 40a and 46b, and line 39 connects into branchlines 41a, 4|b, said branch lines leading to said injectors, as will bemore fully described hereinafter.

Now considering the component parts of the aforesaid describedrefrigeration apparatus, reference is had to Figs. 2, 3 and 4illustrating the details of the improved motor-compressor unit which ismotivated by the high pressure refrigerant vapor generated in the boilerB. As illustratively shown, the motor-compressor unit MC comprises anelongated cylinder 45 closed at its ends by the heads 46, 41, into whichthe previously described compressor discharge lines 26, 21 and thesuction (inlet) lines 36, 31 are connected. The interior cylinder spaceis divided by a central partition 48 in which a connecting rod 49 hassliding bearing, the connecting rod mounting at its ends the pistons 50,5| which accordingly reciprocate in unison, that is to say, as one ofthe pistons 50, 5| is motivated in outward direction by high pressurerefrigerant vapor supplied to its under face, it imparts correspondingtravel to the other piston.

High pressure refrigerant vapor enters one or the other power spaces ofthe cylinder from line 24 through a radial port 52 provided in thepartition 48 and which opens into an annular passage 53 formed in thepartition to encircle and open into a cylindrical cavity or bore 54 fora reversible admission valve 55. Said valve is preferably of thecylindrical plug type and. has shorter length than the valve cavity 54in which it operates, and in its end positions, it controls opening andclosing of the smaller diameter end passages 56, 51 through which thevalve cavity opens into the power spaces of the cylinder, as the termpower spaces is employed to designate the cylinder inner-end spacesbetween the partition and under faces of the pistons 50, 5|.

As best seen in Fig. 4, the admission valve 55 is provided at each endwith a pair of diametrically opposed and axially aligned flats," thealigned flats 58, 59, of the pairs having non-communicating relation dueto the fullcircular central portion of the valve body. Accordingly, whenthe valve 55 is disposed in its leftwise position, as in Fig. 1, highpressure refrigerant vapor is distributed to the innerend space to theright of the partition 48 through port 52, annular passage 53, valveflats 59, right end of valve cavity 54, and the small diameter endpassage 51 to cylinder. Conversely, when the valve 55 has moved to theright, as in Fig. 3, high pressure refrigerant vapor is distributed tothe cylinder inner-end space to the other side of the partition 48through the left end valve flats 58 and cavity end passage 56. Due tothe full circular central portion of the valve body 55, supply of highpressure fluid to either of the cylinder spaces is interrupted as thevalve is in its intermediate or dead-center position, whereby thepossibility of a pressure lock occurring within the cylinder consequentto high pressure fluid being admitted to both power spaces at the sametime is preeluded.

To effect reversing action of the valve 55 requisite to its distributingfunction, it is provided with actuating pins 62, 63 projecting axiallyfrom the ends thereof. The action of said pins in effecting valve travelwill be seen from a comparison of Figs. 2 and 3. In Fig. 2, wherein thevalve is shown in its leftwise end position to which it has beenpreviously actuated by engagement of piston 5| with pin 63, it will beseen that the left-hand pin 62 projects into the power space to the leftof partition 48. As piston 50' moving to the right approaches the end ofits stroke (this piston position being illustrated in Fig. 3), its underface will engage the pin 62 and shift the valve 55 to the right.Righthand pin 63 will now project into the power space to the right ofthe cylinder partition and is thus engageable by the piston 5| as thelatter approaches the limit of its leftwise travel, such engagementeffecting valve reversal and return movement of valve to its Fig. 2position.

The partition 48 also mounts a spool-type reversible exhaust valve 65which, depending upon its axial end position, controls exhaust from thepower or inner-end cylinder space not being supplied with high pressurevapor. Said valve comprises a cylindrical body having enlarged diameterends 66, 61, the body sliding in a cylindrical through passage or boreformed in the partition and which is counterbored at both ends toproseats 68, 69 for the large-diameter valve ends 66, 67. The totallength of the valve 65 is greater than the axial thickness of thepartition :18, and its body portion is provided with opposed fiats" 70,ll (Fig. 4) extending between the enlarged ends 66, 61 of the valve.Said flats provide communication between one or the other of theenlarged counter-bores 68, 69 and an annular passage 73 formed in thepartition to encircle the valve passage and which opens to a radial port14 into which the exhaust line 28a (Fig. l) is connected. The action ofthe exhaust valve 65 will also be seen from a comparison of Figs. 2 and3. In Fig. 2, the valve is shown in its leftwise position to which ithas been previously actuated by piston 5| in its leftwise travel. Insuch position, the power space to the right of the partition 48 is beingsupplied with high pressure refrigerant vapor from the boiler, and suchpressure is effective on the face of the large-diameter right end 61 ofthe valve, whereb said valve is not only seated but its end "61 hassealing eng a'gernent with the internal shoulder tamed by thecounter-bore es. However, the left end of the valve is spaced from itscounter-bore til, with the result that the power or inner-end space toleft of the partition, in which expansion has taken place and theexpanded vapor is be compressed by the under face of piston til which isnow acting as a compression face, may exhaust through the left end ofthe valve to line 2311. Upon piston 5t approachingthe end of its travelto the right, it engages against the enlarged end 66 of the valve andshifts same to the right, closing" the left end of the valve, andpermitting the power space to the right of the partition 48 to exhaustthrough the right end of the valve into exhaust line etc. Asdiagrammatically shown in Figs. 2 and 3, outwardly openingcheck valvesit, I l are provided between the outer-end compression spaces of thecylinder and the discharge lines 26, 2?, respectively, and similar butinwardly opening check valves 13, it are provided between saidcompression spaces and suction lines 3%, 3 respectively.

With the construction so far described, assuming admission valve 55 tobe in its lcftwise position shown in 2, high pressure refrigerant vaporfrom the boiler is beingsupplied to the power space between partitionand under face of piston 51 acting a power piston. and accordinglypiston 53 is actuated to the right, the outer face of the pistoncoinpi'eusing the warm vapor previously drawn into the right outer-endcompression space of the cylinder, the compressed vapor dischargingthrough line 2"! to condenser C, suction line it? being meanwhile closedby check valve 15. The exhaust valve to is also in its leftwiseposition, and the high pressure vapor admitted to the under face ofpiston 51 is also eiiective against the of the enlarged valve end til.Due to the positive connection between pistons 5t, iii provided byconnecting rod ie, piston 5B is also motivated to the right. Check valve78 is open as shown, so that the outer face of the piston 58 functionsas pump face, drawing warm gas from the evapo rator E into the leftouter-end space of the cylinder through line 35, check valve iiimeantime closing off the discharge line 25. The under face of piston isnow also functioning as a compression face, and the expanded vaporcompressed in the left inner-end cylinder space is through the open leftend of valve t5 into errhaust line 28a, this exhaust combining with thecompressed vapor discharging through line 21 and being conducted tocondenser through line 29.

Upon piston 5i! reaching the end of its right-- wise travel, it efiectsreversal of both admission valve and exhaust valve and movement thereofto the right, as seen in Fig. 3. Accordingly, the high pressure vaporboiler is now effective against the under face of the piston 5t, causingit to move to the left and impart corresponding leftwise movement topiston 5|. Leftwise travel of piston to compresses the warm gaspreviously drawn into the compression space at the left outer end of thecylinder through line 35, discharging the compressed vapor through line2'6 to condenser. The under face of piston 51 is now acting as acompression face, the compressed vapor exhausting through valve 65 tolines 28a, 29 and thenceto condenser. The outer face of piston 5| actsas a pump race, drawing the warm vapor from "the evap- 6 orator into theright outer-end of the cylinder. This cycle is repeated at a rate whichvaries with the demands of the system, such corresponding to the rate ofevaporation in the evaporator.

Considering that the pistons 5U, 51, when functioning as co .ipr'essorpistons, are working against condenser pressure which is effective on atotal piston area equivalent to substantially twice the area of a singlepiston face, it becomes obvious that the motivating fluid (high pressurerefrigerant vapor from the boiler) must have a pressure value at leastequal to twice the condenser pre'ssu This disregards evaporator pressureeffective on outer face of the piston then acting as a pump face, butfor the purpose of discussing the principles of the present invention,evaporator pressure, though recognized, can discounted. To insure therequisite high pressure of the refrigerant vapor supplied to the powerspaces of the motor-compressor unit for the reason assigned in theforegoing, the above referred to pressure regulating valve RV isprovided.

Referring to Figs. '7, 8 and 9, illustrating the details thereof, thepressure regulating valve RV preferably comprises a stepped diametercasing 532 having a closed bottom, and being closed at its top s by aplate fit into which line 3i from receiver R is connected. Mounted inthe large-diamcter upper end of the casing is a flexible diaphragm -84defining with the under face of the closure plate '83 a sealed chamberCA which at receiver and hence condenser pressure. li Iounted in thesinali diameter end of the casing is a flexible diaphragm lie defining alower sealed chamber CB into which connects the vapor line ill from theboiler and the vapor line iii extending to the secondary heating chamber22. Accordingly, pressure in chamber CB corresponds to the pressure inthe vapor generated in the boiler B, or more simply, to boiler pressure.

In a system wherein the pressure of the mo tive fluid must be at leasttwice the condenser pressure, the diaphragm 85 has an effective iacearea which is twice that of the diaphragm ts, and said diaphragins areconnected to move in unison by an stem 8i, a depending tubular end sitextending into the chamber CB, which receives a pin as projectingupwardly from a needle valve to. A lost-motion connection is providedbetween the lower end 38 of the stern 87 and the valve pin 9% suchillustratively taking the form or pin and slot connection ill, Q2, whichpermits limited up ward movement of the diaphragm without correspondingupward movcmcnt of needle valve Needle valve 90 operates in the bore ofa tubular end fitting with which line 21 is in communication, thefitting being shaped to provide a conical valve seat 94 for the needlevalve til. An opening 95 the fitting 93 provides communication betweenchamber and line 225, opening being closed when the needle valve iullseate-rl, as illustrated in Figs. 7 and 8 (full lines). The needle valveto normally seated so as to seal off line 2! from line 28 by thepreponderance of pressure inchamber CA, against the bias of a relativelylight spring s6 whose ends react bet-ween the bottom wall or the chamberCB and a radial flange fifia fcu'ined on the valve body int rmediate itsend.

in the circular side wall or- 'poi11te'd valve "end and its pinIntermediate its ends, the diaphragm connecting stem 81 is formed with aknob-like enlargement 9'! functioning as a double wedge cam, andpositioned in the path of travel of said enlargement is a ball 98 whichpartially projects from, although being retained in, the end of atubular retainer sleeve t9, the ball being backed by a spring I whosetension is adjustable by a thumb screw IIlI threaded into said sleeve.The ball 98 bears against the stem enlargement M with spring pressureand it serves, in conjunction with said enlargement to exercise aholding action on the stem when the latter moves to one or the other ofits extreme positions as illustrated in Figs. 7 and 9, consequent to asubstantial decrease of pressure in one or the other of the chambers CAor CB.

The functioning of the regulating valve will now be briefly analyzed. Ifboth the pilot and the main burners I3, i2, respectively, are unlighted,pressure in chamber CB is of course low and needle valve 90 is closed onits seat 93 by the relatively high condenser pressure effective ondiaphragm 25, so that the apparatus is completely inoperative eventhough the thermostat T associated with the evaporator may call forcooling. Consequent to the low pressure in chamber CB, the diaphragmstem 8! will be actuated to its low position illustratively shown inFig. '7, the ball 98 thereupon exercising holding action on said stern.Such arrangement provides a valuable safety feature in that the systemis rendered inoperative if the pilot light should be extinguishedaccidentally.

Normally, however, the pilot burner I3 is lighted and its adjustment issuch that it pro vides sufiicient heat for the boiler to vaporize theliquefied refrigerant to a predetermined normal operating pressure whichis such as to result in a predetermined pressure difference obtaining inthe chambers CA and CB. Under this condition of predetermined pressuredifference, diaphragms 84 and S5 assume their normal operating i. e.balanced position illustrated in full lines, Fig. 8, but needle-valve 88remains closed as permitted by the pin and slot connection 9!, 92between tubular end 88 of the diaphragm connecting stem 8'! and theupwardly projecting valve pin 89. In said position, ball 98 bears on theupper middle zone of the stem enlargement 9?, having been plied to theright by the cam action of said enlargement, and the system isaccordingly conditioned for operation upon the thermostat T calling forcooling,

If, now, the thermostat '1 calls for cooling, fuel metering valve lvlVbecomes effective, as will be described, immediately to supply fuel tothe main burner I2 through line I254. Additional heat is accordinglysupplied to boiler B, thereby increasing the rate of vaporization andthe pressure within the boiler 13. This increased pressure becomesalmost immediately effective in chamber CB and causes slight upwardmovement of the diaphragms 8d, :35 and stem 87, which slightly raisesthe stem enlargement 9'! to its dotted line position (Fig. 8) and alsoeffects limited upward or unseating movement of valve 90, as thepermissible relative movement between stem 8i and valve 90 as providedby the lost motion connection 9I, 92 has now been exceeded. Upon theneedle valve 90 being raised from its seat, spring 96 becomesimmediately effective, and snaps said valve to full open position.Accordingly, full volume of high pressure vapor from chamber CE 8 maynow pass through the valve into line 2| and thence to motor-compressorunit MC, placing the same in operation. As valve opening movement underthe urge of spring 96 as aforesaid is independent of diaphragm and stemmovement, said diaphragms maintain a working position in which the fullmiddle zone of the stem enlargement 9! is engaged by the ball 98. Thus,assuming the demand for cooling to continue, there results a regulatedsupply of high pressure vapor being passed through the regulating valveRV to the motor-compressor unit, and the latter thereby operates at arate determined by the cooling effect called for by the thermostat T.

However, should pressure within the boiler tend to build up to unsafelimits, the diaphragms 84, and connecting stem 81 also tend to moveupwardly to the position shown in Fig. 9. Once this move has beeninitiated, the ball 98 exercises camming effect on the lower roundedsurface of the stem enlargement 91 and thereby completes raisingmovement of stem and diaphragms. This full raising movement of thediaphragms and stem maintains full communication between lines 20, 2|irrespective of cooling requirements,

and, as will be described, also cuts off the supply of gas to the mainburner I2 until pressure in chamber CB lowers sufilciently toreestablish the normal difference in pressure in the chambers CA and CB,whereupon the system operates in the manner above described in responseto a demand for cooling.

From the above general statement of fuctioning, it will be observed thatwhile the pressure regulating valve RV regulates the pressure of therefrigerant vapor supplied to the motor-compressor unit, the primarycontrol for normal operating conditions is exercised through the rate atwhich fuel is supplied to the main burner I2, through fuel meteringvalve MV, responsively to the rate of evaporation in the evaporator E,as through the temperature control TC. However, it is a feature of theinvention that the regulating valve RV exercises supervisory control onthe fuel supply to burner I2, and to permit a clearer understanding ofthe integration between the regulating valve, the metering valve, andthe system controls, the metering valve will now be described in detail.

Referring to Figs. 5 and 6, the aforesaid fuel metering valve MVpreferably comprises a cylindrical, step-diameter housing I05 having aninterior partition I08 dividing the housing into chambers IEl'II, I138.The large-diameter end of the casing is closed by a face plate I09 intowhich connects the fuel supply line SL. Communication between chambersI01 and Hit is provided by an opening H9 in the partition I65, which isnormally closed by a disc-valve II I illustratively shown to be mountedat one end of a leaf spring I I2 contained in housing I07, the other endthere? of being fixed generally as shown. Gas line I3a to pilot burnerI3 is also connected into the face plate I09 so as to communicate withchamber I07 thereof, whereby gas from the supply line SL- passes at aconstant low rate through gas line 13a to the pilot burner I3. Discvalve III is adapted to be opened against the bias of spring II2 uponleftwise movement of a pointed stem,

I I3 mounted on the axis of the housing chamber I98 and carried by andto one side of a flexible sealing diaphragm H4 extending across it, the

stem having an enlarged boss-like end II5 exv tending to the other sideof the diaphragm I I4.

The small diameter. end of the valve housing also mounts externallythereof a thermostat diaphragm H6 sealed within an enclosure II'I, thediaphragm being responsive to expansion and contraction of aheat-sensitive medium contained in the space above the diaphragm and ina capillary li'I extending to the thermostat T associated withevaporator E, said parts being collectively referred to ,as thethermostat control TC. The diaphragm I6 bears on a pin I2!) journaledfor limited sliding movement through the side wall of the small diameterend of the housing IE8 and whose upper end projects into the diaphragmenclosure I I! to engage with said diaphragm. The pin I is biased inupward direction by means of a coaxially disposed springloaded pin I 2!acting on the lower end of the pin I20 through the intermediary of aball I22. Said pin I2I is springeloaded by a spring I23 operating in asleeve I24 into which an adjusting thumb screw I25 is threaded, saidadjusting screw providing a simple means for adjusting the pressure atwhich deflection of diaphragm H6 is effective to cause downward movementof pin 525 against the bias of spring I23.

According to the invention, the valve I II controlling supply of fuel tothe main burner I2 is opened upon the evaporator thermostat T callingfor cooling, and provided the normal pressure difference obtains inchambers CA and GB of regulating valve RV. To satisfy such requirement,a control rod I28 of the referred to supervisory control SC extendsbetween regulating and metering valves, the rod operating in a sleeveI29. The right end of the rod and sleeve projects into the regulatingvalve casing 52, said sleeve end mounting a ball I38 which closely abutsthe end of the control rod and engages against stem enlargement Bl,being aligned with the previous described ball 98, having similarengagement.

The other or left end of the control rod I28 ing valve RV, said controlrod end-ball I32 is disposed in the path of movement of the ball E22, asseen in Fig. 6.

Thus, upon the thermostat T calling for cooling, diaphragm I I t isdistended downwardly, and

pin I211 is also forced downwardly, such forcing ball I22 downwardlyinto alignment with ball I32 at the metering valve end of the controlrod I28, the position of the latter being considered fixed under thecondition of the normal pressure difference obtaining in the chambers ofthe regulating valve. Such downward movement of ball I22 causes it to becamnied to the left by ball I32, whereupon it engages against theenlarged end H5 of the valve actuating stem I I3, causing leftwisemovement thereof which results in opening of the valve III. Accordingly,fuel may pass through the metering valve to the main burner I2 inaccordance with the cooling efiect called for.

In the event the pilot burner I3 has become accidentally extinguished,or if the pressure in chamber CB of the regulating valve has exceededsafe limits, control rod I23 may move freely to the right the limiteddistance permitting the thermostat actuated ball I22 to lower withoutforcing the stem H3 against valve Ill. Thus, even if the thermostatcalls for cooling under the above conditions, valve IE I remains closed.Hence, it will be seen that the regulating valve RV exercises asupervisory control over the functioning of the fuel metering valve byinsuring the supply of fuel to the main burner only under the normalcondition of predetermined pressure (iii-Terence obtaining in theregulating valve, or under the operating condition of said pressuredifference not substantially exceeding the predetermined difference.

As previously forecast, the injectors I1, I2 are operated alternately tosupply make-up liquid to the boiler B by the difference in pressureofthe refrigerant vapor in the motor-compressor unit MC. Referring toFigs. 10 and i1, illustratingthe construction and operation of theinjectors, each comprises a thickewalled cylinder, of which cylinder ofinjector I1 is designated I35 and the cylinder of injector Is isdesignated I35. Both saidcylinders may be provided with heat dissipatingfins I37, I38 formed by circumferential grooves in the mid portions ofthe cylinders. The cylinder I35 is closed at its ends by an upper endmember I39 and a lower end member Hit, the cylinder I36 being closed bysimilar end mem bers ItI, I42. The cylinder I35 is provided with avertically disposed plunger bore Idii opening at its lower end into avalve cavity Hi4 pr vided in the bottom end member lit and in its upperend into a piston bore I which is closed at its upper end by the endmember I39. The cylinder IE5 is provided with a similar plunger bore It!opening at one end to valve cavity will in end member I42 and at itsother end to piston bore I59 closed at its upper end by end member MI.

, Mounted to reciprocate in the piston and plunger bores of injectorcylinder IE5 is an interconnected pistonIBil and plunger I5i, and asimilar interconnected piston and plunger I52, I53 is mounted inthe-piston and plunger bores of the injector cylinder I36- Disposed inthe cavity M4 is checli valve Hi5, preferably of disc form, which isbiased to its raised (closed) positionyby an annular spring I56 providedwith flexible valve supporting fingers. Disposed in cavity Hill is asimilar disc valve I5"! biased to its closed position by an annularspring Hill similar to spring I56.

The previously described branch line Alla of the take-oi? line 33 whichis connected to the innerend space of motor-compressor cylinder to theleft of the partition til thereof is connected into the upper end memberI324 of the injector cylinder I 35 to supply high pressure refrigerantvapor to the upper face of piston IEI'i, and branch line 4% is connectedto the cylinder I36 at a point thereof as simultaneously to supply highpressure vapor to the under face of piston I52. Branch line Ma fromtake-on line 39 conducts the high pressure refrigerant vapor from thecylinder inner-end space to the right of partition 48 to cylinder I35 ata point thereof so as to supply high pressure vapor to the under face ofpiston ifiil, the other branch line lib being connected into upper endmember MI of cylinder I36 so as to supply vapor to the upper face ofpiston I49. The liquid line I 8 through which liquefied refrigerant fromreceiver R is conducted to the injectors is connected at its ends intothe plunger bores M3 and it! of the respective cylinders, connectionbeing made at a point thereof immediately below the end face of theplungers Itl, I53

when the latter are in their uppermost position. The liquid make-uplines IE, IS connect into the cavities I44, I43, respectively, of thecylinder end members I40, I42.

Assuming high pressure refrigerant vapor being admitted to the cylinderspace to the right of partition 48 of the motor-compressor cylinder,such high pressure vapor is conducted through take-off line 39 andbranch lines Ma, Mb simultaneously to the under face of piston I50 andthe upper face of piston I52. Although refrigerant vapor is beingsupplied also to the upper face of piston I50 and the under face ofpiston I52 through take-off line 38 connected to the cylinder space tothe left of said partition 48, the pressure therein is lower than in thecylinder space to which the high pressure vapor from the generator isbeing supplied, due to the fact that expansion has occurred in theformer cylinder space. Accordingly, piston I50 is motivated upwardly andpiston I52 is motivated downwardly, with corresponding movement beingimparted to the piston plungers I I, I53. As piston plunger I5I movesupwardly, it draws a charge of liquefied refrigerant from line I0 intoits bore and, as plunger I53 moves downwardly, it forces the charge ofliquefied refrigerant previously drawn into its bore past valve I51 andto the boiler B through make-up line I6. Upon reversal of the valve 55of the motor-compressor unit being effected, the reverse action takesplace, namely, the injector piston I50 is driven downwardly to force thecharge of liquefied refrigerant contained in bore I 43 past the valveI55 to make-up line I5, and the piston I52 is driven upwardly to draw acharge of liquefied refrigerant into the lower end of its bore I41.Since the rate at which the injectors I1 and I2 operate depends on therate of operation of the motor-compressor unit, and as the latterdepends on the rate of cooling called for by the thermostat T, it willbe seen that makeup refrigerant in liquefied form is supplied to theboiler B in accordance with the rate of evaporation in the evaporator E.

Refrigeration apparatus as described in the foregoing, in which a singlesupply of refrigerant, such as Freon serves as the working fluid for themotor-compressor unit, provides many practical advantages. The apparatusmay be made substantially smaller and more compact than conventionalrefrigeration aparatus while at the same time giving at least equalrefrigeration service. It is self-lubricating by simply admixing ordissolving oil in the refrigerant. The motorcompressor may be built as acompletely sealed unit with no leakage. It permits of reduction in sizeof the condenser consequent to high efficiencies attained, and of theelimination of electric motors for both compressor and condenser coolingfan. Another advantage of the improved refrigeration system resides inits substantially noiseless operation.

As many changes could be made in carrying out the above constructionswithout departing from the scope of the invention, it is intended thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

I claim:

1. In refrigerating apparatus employing a compressor-condenser-expandercircuit and utilizing high-pressure vaporized refrigerant as the motivefluid, a fluid motor-compressor-pump unit comprising a cylinder havingend closures and a transverse partition subdividing its interior space,pistons mounted for reciprocatory travel in the cylinder end-spaces, apiston rod having sliding bearing in the partition and interconnectingsaid pistons for movement in unison, means for distributinghigh-pressure vaporized refrigerant through the partition alternately tothe cylinder inner-end spaces thereby to motivate said pistonsalternately throughout their compression strokes, means for exhaustingthe cylinder innerend space not then being supplied with the vaporizedrefrigerant through the partition, whereby the piston operating in saidspace is actuated throughout its combined pump and exhaust stroke by thepiston moving throughout its compression stroke, valved conduitsconnected to the cylinder end-closures for admitting low pressurevaporized refrigerant into the cylinder outer-end spaces under thesuction effect of the pistons as the latter move throughout theirexhaust stroke, and valved conduits connected to the cylinderend-closures for delivering the refrigerant compressed by the pistons asthe latter are motivated throughout their compression strokes to thecondenser.

2. Refrigerating apparatus as set forth in claim 1, wherein the meansfor exhausting the cylinder inner-end spaces and the compressedrefrigerant conduits are connected into a common line delivering to thecondenser.

3. Refrigerating apparatus as set forth in claim 1, wherein thedistributing and exhaust means are actuable by the pistons upon thelatter approaching the end of their exhaust strokes.

4. Refrigeration apparatus comprising a fluid motor-compressor unit, acondenser and an evaporator, said motor-compressor unit comprising acylinder having a central partition, pistons interconnected toreciprocate in unison within the opposite ends of the cylinder uponmotive fluid being supplied alternately to the adjacent under faces ofsaid pistons, the cylinder being closed at its ends and suitable valvedconnections be tween the cylinder outer-end spaces and each of saidcondenser and. evaporator, whereby the outer faces of the pistonsfunction alternately as compression and pump faces, the cylinderinner-end spaces being connected to condenser whereby the underface ofthe piston not being supplied with motive fluid also functions as acompressor face, means for vaporizing under relatively high pressure acontrolled portion of the refrigerant liquefied in the condenser, andmeans for supplying the high pressure refrigerant vapor alternately tothe working faces of said pistons.

5. Refrigeration apparatus comprising a fluid motor-compressor unit, acondenser and an evaporator, said motor-compressor unit comprising acylinder having a central partition, pistons interconnected toreciprocate in unison within the opposite ends of the cylinder uponmotive fluid being supplied alternately to the adjacent under faces ofsaid pistons, the cylinder being closed at its ends and suitable valvedconnections between the cylinder outer-end spaces and each of saidcondenser and evaporator, whereby the outer faces of the pistonsfunction alternately as compression and pump faces, the cylinderinner-end spaces being connected to condenser whereby the under face ofthe piston not being supplied with motive fluid also functions as acompressor face, means for vaporizing a portion of the refrigerantliquefied in the condenser under a sufficiently high pressure: that itWill motivate the one; piston on which it is eilective againstthe.condenser pressure effective on the two faces; of the pistons thenfunctioning as compression faces, and means for supplying therefrigerant vapor at the aforesaid ll'gh pressure alternately to theWorking faces of said cylinders.

6. Refrigeration apparatus as set. forth in claim combined with meansactuated by the high pressurev refri erant vapor for supplying make-upliquefied refrigerant to the vaporizing means for vaporization therein.

'7. Refrigeration apparatus as set forth in claim & combined with meansfor supplying liquefied refrigerant from the condenser to the vaporizingmeans, said last means being actuaole by the clifference in pressureeffective on the underfaces of said pistons.

8. Refrigeration apparatus as set forth in. claim 4, wherein said vaporsupplying means includes a reciprocating valve actuable by said pistonsin their reciprocation.

9. Refrigeration apparatus as setforth in claim 4:, wherein said vaporsupplying means includes a reversing valve mounted in the cylinderpartition and being actuaole to reverse positions by said pistons.

10. Refrigeration apparatus as set forth in claim 4:, wherein said lastmeans includes a reversing valve mounted in the cylinder partition so asto be actuable to reverse positions by said pistons in which it admitsthe high-pressure vapor to one or the other cylinder inner-end spaces,said valve being operative in its intermediate position to positivelyinterrupt admission to both said spaces.

11. Refrigeration apparatus as set forth in claim l, wherein first andsecond reversible valve means mounted in the cylinder partitions so tohe aotuable to reverse positions by said pistons, the first valve meansbeing operative to ad Init the high pressure vapor to one cylinderinnerend space for expansion therein and the second valve means beingoperative simultaneously to exhaust the expanded vapor being compressedin the other cylinder inner-end space to condenser.

12. In heat-operatecl refrigeration apparatus, a fluidinotoncorlngressor unit, condenser and an evaporator, a boiler suppliedwith liquefied refrigerant from the condenser and operating to vaporizea controlled portion of the liquefied releans effective to supply thevaporrefr' ant at a predetermined working pressure to themotor-compressor unit, and means for controlling the actuation. of theheating means, last means being jointly responsive to the rate ofevaporation in the evaporator and to any deviation in the pressure ofsaid vaporized refrigerant from the predetermined Working pressure.

13. In heat-operated refrigeration apparatus, a fluid motor-compressorunit, a condenser and an evaporator, a boiler supplied with liquefiedrefrigerant from the condenser and operating to vaporize a controlledportion of the liquefied re- -irigerant, heating means for the boilercomprising pilot and main burners and fuel supply lines thereto and afuel metering valve normally closing the supply line to main burner andoperative to supply a constant low volume of fuel to the pilot burn-erwhich is such as to effect vaporizetion of the liquid refrigerant to apredetermined normal pressure, pressure regulating means for regulatingthe pressure of the vaporized refrigerant and being effective to supplyrefrigerant vapor at a Working pressure in excess or the normal pressureto the motor-compressor unit, and means responsiveto the rate ofevaporation in the evaporator and the maintenance of the predeterminednormal pressure for actuating said metering valve to open the fuelsupply line to the main burner.

14. In heat-operated refrigeration apparatus, a fluid llfiOlJGI'COlllFQFJQSSOl unit, a condenser and an evaporator, a boiler suppliedwith liquefied refrigerant from the condenser and operating to vaporizea controlled portion of the liquefied refrigerant, heating means for theboiler, a pressure regulating valve means connected between boiler andmotorompressor unit for supplying the vaporized ref" erant to thelatter, said valve means responding to both condenser boiler pressuresand being operative to establish predetermined high pressure of thevaporized rigerant supplied to the motor-oolnnresso.= unit relative tocondenser pressure, means i? 1' controlling the heating meansresponsively to the rate of evaporation in the evaporator, andsupervisory control means actuable by the pressure regulating valvemeans to render first control means ineffective upon the heating meansbecoming inoperative or upon the boiler pressure substantially exceedingsaid predetermined pre sure.

15. In heat-operated refrigeration apparatus, a fluid rumor-compressorunit, a condenser and an evaporator, a boiler supplied with liquefiedrefrigerant from the condense and operating to vaporize a controlledportion of the liquefied 'efrigerent, heating means for the boiler, apresure-regulating valve means connected between oiler andmotormompressor unit for supplying the vaporized refrigerant to thelatter, valve means including a large area diaphragm responsive tocondenser pressure, a second smallarea diaphragm responsive to hollerpressure, a stem connecting said diaphragm whereby they move in unison,and a valve element controlling passage of the vaporized refri lraut tothe motor-compressor uni the valve element having a lost-1notlonconnection with stem providing for movement of diaphragms and stem to anormal position Without corresponding opening movement or the valve elin which normal position the boiler pressure exceeds the condenserressure by a predetermined amount determined by the difference in theareas of said diaphragm heating being adjusted normally to supply heatto the boiler sufl'ioient to maintain said normal position of saiddiaphragms, responding to the rate or" evaporation at the evaporator forsupplying addi tional heat to the boiler resulting in increased boilerpressure and thereby corresponding further movement of said diaphragmsand limited opening of said valve elel lent, and spring means associatedwith said valve element for actuating said valve element to full openposition upon its opening movement being initiated, as aforesaid,thereby to supply a full volume of vapor at the increased boilerpressure to the motor-coll= pressor unit.

16. Heat-operated refrigeration apparatus as set forth in claim 13,wherein said pressure regulating means includes a first large-areadiaphragm responding to condenser pressure, a second smaller-areadiaphragm responding to boiler pressure, said diaphragms being connectedto move in unison by a stem having a cam-like enlargement thereon, saidpilot burner being adjusted so as normally to supply sufficient heat tothe boiler to maintain the predetermined normal pressure of thevaporized refrigerant, and wherein the means for actuating the meteringvalve to open position includes a valve actuating element, a membermovable responsively to the rate of evaporation in the evaporator froman in active to an active position in which it is conditioned to actuatesaid valve actuating element, and a supervisory control member actuableby said stem enlargement to a position in which it is effective totranslate movement of said movable member to active position into motionof said valve actuating element and opening of said metering valve.

17. In heat-operated refrigeration apparatus. a fluid motor-compressorunit, a condenser and an evaporator, a boiler supplied with liquefiedrefrigerant from the condenser and operating to vaporize a controlledportion of the liquefied refrigerant, heating means for the boiler,pressure responsive means effective to supply the vaporized refrigerantat a predetermined working pressure to the motor compressor unit, meansfor supplying fuel to the heating means in accordance with the demandfor evaporation in the evaporator, and means for inter-relating theactuation of the fuel supplying means with that of the pressureresponsive means.

18. In heat-operated refrigeration apparatus, a fluid motor-compressorunit, a condenser and an evaporator, a boiler supplied with liquefiedrefrigerant from the condenser and operating to evaporate a controlledportion of the liquefied refrigerant, heating means for the boilercomprising pilot and main burners and fuel supply lines thereto and afuel metering valve normally closing the supply line to main burner andoperative to supply a constant low volume of fuel to the pilot burnerwhich is such as to effect vaporization of the liquid refrigerant to apredetermined normal pressure, pressure regulating means for regulatingthe pressure of the vaporized refrigerant and being effective to supplyrefrigerant vapor at a working pressure in excess of the normal pressureto the motor-compressor unit, means for actuating the fuel meteringvalve to open and supply line to main burner in response to a demand forevaporation in the evaporator, and means inter-relating the actuation ofsaid last means with that of the pressure regulating means in suchmanner that the fuel 16- metering valve is operative to open said supplyline to main burner only upon the predetermined normal pressure of therefrigerant having first been established.

19. Refrigeration apparatus comprising a fluid motor-compressor unit, acondenser, and an evaporator, said motor-compressor unit comprising acylinder having a central partition, pistons interconnected toreciprocate in unison in the opposite ends of the cylinder, both theouter and the inner end spaces of each cylinder end being connected tothe condenser, the arrangement being such that the pistons are motivatedby working fluid supplied alternately to the underfaces of the pistonsat a pressure sufficiently that the under-face of the piston not beingsupplied with working fluid acts as a compression face for deliveringthe expanded fluid previously supplied thereto as the working fluid tothe condenser, a boiler for vaporizing a portion of the liquefiedrefrigerant under a pressure which is sufficiently high as to motivatethe piston against the condenser pressure effective on the two pistonfaces then acting as compression faces, means for supplying the highpressure refrigerant vapor alternately to the inner-end spaces of saidcylinder, and means for supplying liquefied refrigerant from thecondenser to the boiler comprising a pair of injectors each including acylinder, a power piston and a plunger actuated by said piston to draw acharge of liquefied refrigerant into the cylinder bore and thereupon toforward said charge to boiler, a branched take-off line connecting eachinnerend cylinder space of the motor-compressor unit with both injectorcylinders, the branches of each line delivering to the opposite faces ofthe two power pistons, whereby said power pistons are actuated inopposite directions by the difference in the pressure of the refrigerantvapor existing in said inner-end cylinder spaces.

CARL D. RUSSELL.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 871,325 Coleman Nov. 19,, 1902 1,871,244 Steuart Aug. 9, 19322,411,347 Trumpler Nov. 19, 1946 FOREIGN PATENTS Number Country Date 534Great Britain 1900 2,742 Great Britain 1901

